Five-tier model may allow for more precise prostate cancer treatment

Researchers at the Cambridge University Hospitals system in Britain has developed a five-tied model to assess the seriousness of prostate cancer. Photo by John Liston/Flickr

March 16 (UPI) -- The Cambridge University Hospitals system in Britain has developed a five-tied model that will help medical personnel better treat prostate cancer patients.

The model, called the Cambridge Prognostics Group model, it will help doctors to better distinguish the so-called aggressive "tiger" cancers, the sleeping "pussycats" and those falling somewhere in the middle. Their findings will be presented at the European Association of Urology Congress in Copenhagen, Denmark, this week, as well as in BMC Medicine.

By studying the different tiers, researchers say patients and consultants can determine the best way to manage a condition that can include radiotherapy, surgery or active surveillance.

The researchers report that their five-tier model is consistently superior to the three-tier system currently recommended that has 60 percent accuracy. The tool can calculate a man's chances of dying from prostate cancer with 90 percent accuracy, they report.

For one-third of prostate patients, it's not advantageous to have an aggressive treatment. But a fifth of men with the most aggressive cancers were 20 times more likely to die of prostate cancer within 10 years than those with the least aggressive.

"We are not telling men, you have no risk, you do not need treatment," Vincent Gnanapragasam, an uro-oncology lecturer at the University of Cambridge and Urological Malignancies director co-lead at the Cancer Research UK Cambridge Center, told the Express. "We are telling them, these are the facts."

The analysis includes a man's age, medical history, blood test and biopsy results, and gives a personalized chance of surviving 10 years.

"The beauty of it is that the CPG model has zero costs and is easy to reference as it exploits routinely collected and standardized diagnostic data," Gnanapragasam said in a press release. "We propose the adoption of the CPG model as a simple to use but more accurate stratification tool to help guide management for men with newly diagnosed non-metastatic prostate cancer."

England's National Institute of Clinical Excellence has received the data for consideration of adoption as a national best practice, he said.

The study verifying the model involved more than 75,000 men. They first studied nearly 12,000 men in Britain, and then retested the model in Switzerland with 72,337 Swedish men and 2,550 from Singapore.

"The increasing appreciation that each type of cancer is made up of numerous subtypes, each likely to need different treatments, is transforming the way patients with cancer are managed," said Richard Gilbertson, director of the Cancer Research UK Cambridge Institute.

Last year, Gnanapragasam also developed a new prostate biopsy device called Camprobe.

"Some newly diagnosed tumors will be aggressive -- while many others will have an indolent natural history," he said. "Understanding the likely progress is critical for giving patients precise information tailored to their own situation and for planning management. This model is a significant improvement on how we have done this historically and we can now predict a cancers' likely behavior with a very high degree of accuracy."